The present invention relates to a karaoke amplifier suitable for a karaoke machine.
In the field of the karaoke machine, a karaoke amplifier is used to adjust parameters of microphone inputs, volume of music sounds and various sound effects according to setup positions of analog operation keys. Generally, in the karaoke amplifier, voltage values (analog amounts) corresponding to the setup positions of the analog operation keys are converted into digital values by an A/D (analog/digital) converter. According to the digital values, the karaoke amplifier adjusts a volume and a tone of vocal sounds and instrumental accompaniment sounds of a karaoke performance, and further controls various acoustic effects of the sounds such as an echo level.
However, since characteristics of volumes, tones, and sound effects delicately vary dependently on a sound field condition of a room in which the karaoke amplifier is installed. Further, the acoustic characteristics of the karaoke sounds depend on performance of loudspeakers and so forth. Thus, an initial operation range of the analog operation keys that has been fixed before factory shipment may not be an optimal range of the control parameters.
Moreover, after the karaoke amplifier was delivered to a user, if specifications thereof are changed, it is necessary to change the initial operation range of the analog operation keys. Unless otherwise, the relation between the operation range of the analog operation keys and a required adjustment range of the parameters may not match with each other.
In addition, in the field of a communication type karaoke machine, there are needs to adjust various parameters of the karaoke amplifier according to musical sound control information contained in MIDI (Musical Instrument Digital Interface) data supplied from a host computer by telecommunication.
However, in the conventional karaoke amplifier, there is no means to adjust the parameters other than operating the analog operation keys. Thus, the conventional karaoke amplifier cannot deal with the above-described situation and requirement.